• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.9
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• pp.1133-1138
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• 2006

Smilax china root has been used as traditional medicinal remedy in China and Korea and reported to have various biological activities such as anti-inflammatory, antimutagenic and antimicrobial activities. In this study, the possibility of development as natural antioxidants of Smilax china root extracts was investigated. For the evaluation of antioxidant activity, aqueous- and 25% EtOH extract from Smilax china root were prepared and six different evaluation assay methods, i.e., measurement of total phenolics, radical scavenging effects on 1,1-diphenyl-2-picrylhydrazyl (DPPH), nitric oxide (NO) and nitrite $(NO_2)$, reducing power, and inhibitory effect on tyrosinase activity, were used. The total phenolics content of two extracts was high as the level of 36 mg of gallic acid equivalent per 1 g of dried sample tested. The radical scavenging activities of ethanol extract toward DPPH and NO were better than those of aqueous extract (p<0.05). The $NO_2$ scavenging activity of both extracts showed the highest value at pH 1.2 (98%). Especially, the $NO_2$ scavenging activities of EtOH extract were significantly stronger than those of aqueous one at pH 4.2 (51%) and pH 6.0 (32%), respectively. In the reducing power test, both extracts revealed higher ferric ion reducing activity than known antioxidant, vitamin C at the level of $0.05\sim0.1mg/mL$ (p<0.01). The 1 mL of aqueous and 25% EtOH extract showed effective inhibition activity on tyrosinase activity as 45% and 53%, respectively. Therefore, these results suggest that two extracts from Smilax china root may serve as useful natural antioxidants.

• Korean Journal of Remote Sensing
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• v.14 no.4
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• pp.353-365
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• 1998

Light absorption coefficient per unit mass of particles, i.e., specific absorption coefficient, is important as one of the main parameters in developing algorithms for ocean color remote sensing. Specific absorption coefficient of chlorophyll ($a^*_{ph}$) and suspended sediment ($a^*_{ss}$) were analyzed with a spectrophotometer using the "wet filter technique" and "Kishino method" for the seawater collected in the Yellow and Mediterranean Sea. An improved data-recovery method for the filter technique was also developed using spectrum slopes. This method recovered the baselines of spectrum that were often altered in the original methods. High $a^*_{ph}({lambda})$ values in the oligotrophic Mediterranean Sea and low values in the Yellow Sea were observed, ranging 0.01 to 0.12 $m^2$/mg at the chlorophyll maximum absorption wavelength of 440 nm. The empirical relationship between $a^*_{ph}$(440nm) and chlorophyll concentrations () was found to fit a power function ($a^*_{ph}$=0.039 $^{-0.369}$), which was similar to Bricaud et al. (1995). Absorption specific coefficients for suspended sediment ($a^*_{ss}$) did not show any relationship with concentrations of suspended sediment. However, an average value of $a^*_{ss}$ ranging 0.005 - 0.08 $m^2$/g at 440nm, was comparable to the specific absorption coefficient of soil (loess) measured by Ahn (1990). The morepronounced variability of $a^*_{ss}$ than $a^*_{ph}$ was determined from the variable mixing ratio values between particulate organic matter and mineral. It can also be explained by a wide size-distribution range for SS which were determined by their specific gravity, bottom state, depth and agitation of water mass by wind in the sea surface.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.3
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• pp.408-414
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• 2011

The purpose of this study was to find out optimum cultivated regions for rice organic farming. The organic and conventional rice as control were grown in three different places : secluded hill paddy field for Hapcheon, normal rural paddy field for Sancheong, and suburban paddy field for Jinju from 2005 to 2006. In secluded hill paddy field, the organic material and pesticide to control pest and disease were input twice for organic and conventional rice cultivation. However, in normal rural and suburban paddy field, those were input three times for organic and conventional rice cultivation. The occurrence of sheath blight in organic farming was higher than in conventional farming. Whereas brown planthopper population per 20 plant was significantly high 10.1~19.5 for conventional farming compared with 4.4~10.0 for organic farming. For that reason, the density of the brown planthoppers was higher in organic farming than those in conventional farming. Dominated weeds occurred in organic and conventional paddy field were namely Monochoria vaginalis, Ludwigia prostrata, and Cyperus difformis. The population per 20 plant and dried weight per $m^2$ of weeds were higher in 121 and 50.5 g for organic paddy field. The productivity of rice in different cultivated regions for organic farming was $2.96Mg\;ha^{-1}$ in hill paddy field, $4.03Mg\;ha^{-1}$ in normal rural and suburban paddy field. Toyo-taste value and ratio of perfect grain of milled rice were not different by cultivated regions in both farming system.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.5
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• pp.385-392
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• 2009

This study was conducted to reclassify Namweon series, black volcanic ash soils, in Jeju Island based on the second edition of Soil Taxonomy : A Basic System of Soil Classification for Making and Interpreting Soil Surveys. Morphological properties of typifying pedon of Namweon series were investigated and physicochemical properties were analyzed according to Soil Survey Laboratory Methods Manual. The typifying pedon of Namweon series has black (10YR 2/1) silt loam Ap horizon (0~11 cm) and black (10YR 2/1) silt loam BA horizon (11~72 cm). Bw horizon (72~100 cm) is very dark brown (10YR 2/2) silt loam. That occurs on lava plain derived from volcanic ash materials. The typifying pedon contains 5.2~6.4% oxalate extractable (Al + 1/2 Fe), over 85% phosphate retention, and lower bulk density than $0.90Mg\;m^{-3}$. Ap, BA, and Bw horizons of the pedon have andic soil properties. That can be classified as Andisol. The typifying pedon has an udic soil moisture regime and has a 1,500 kPa water retention of 15% or more on air-dried samples throughout all horizons, and can be classified as Udand. Ap and BA horizons (0~72 cm) have a color value, moist, and chroma of 2 or less, melanic index of 1.70 or less, and 6% or more organic carbon. That meets the requirements of melanic epipedon. That keys out as Melanudand. That has more than 6.0% organic carbon and the colors of mollic epipedon throughout a layer 50 cm or more thick within 60 cm of the mineral soil surface.. Thus, that keys out as Pachic Melanudand. The pedon has a fine-earth fraction that has a water content at 1,500 kPa tension of 12% or more on air-dried samples and has less than 35% (by volume) rock fragments. Thus, the substitute for particle-size class is medial. That has a sum of 8 times the Si (percnt by weight extracted by acid oxalate) plus 2 times the Fe (percnt by weight extracted by acid oxalate) of 5 or more, and 2 times the Fe is more than 8 times the Si. Thus, the mineralogy class is ferrihydritic. Namweon series can be classified as medial, ferrihydritic, thermic family of Pachic Melanudands, not as ashy, thermic family of Typic Melanudands.

• Journal of the Korean Society of Radiology
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• v.15 no.6
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• pp.781-788
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• 2021

Due to the high sensitivity to radiation, excessive exposure needs to be prevented by accurately measuring the dose irradiated to the skin during radiation therapy. Although clinical trials use dosimeters such as film, OSLD, TLD, glass dosimeter, etc. to measure skin dose, these dosimeters have difficulty in accurate dosimetry on skin curves. In this study, to solve these problems, we developed a skin dosimeter that can be attached according to human flexion and evaluated its response characteristics. For the manufacture of the dosimeter, lead oxide (PbO) with high atomic number (Z_Pb: 82, Z_O: 8) and density (9.53 g/cm³) and silicon binders that can bend according to human flexion were used. In the case of a dosimeter made of PbO material, the performance degradation has been prevented by using parylene and others due to the presence of degradation due to oxidation, but the previously used parylene is affected by bending, so a new form of passive layer was produced and applied to the skin dosimeter. The characteristic evaluation of the skin dosimeter was evaluated by analyzing SEM, reproducibility, and linearity. Through SEM analysis, bending was evaluated, reproducibility and linearity at 6 MeV energy were evaluated, and applicability was assessed with a skin dosimeter. As a result of observing the dosimeter surface through SEM analysis, the parylene passive layer PbO dosimeter with the positive layer raised to the parylene produced cracks on the surface when bent. On the other hand, no crack was observed in the silicon passive layer PbO dosimeter, which was raised to silicon passive layer. In the reproducibility measurement results, the RSD of the silicon passive layer PbO dosimeter was 1.47% which satisfied the evaluation criteria RSD 1.5% and the linearity evaluation results showed the R² value of 0.9990, which satisfied the evaluation criteria R² 9990. The silicon passive layer PbO dosimeter was evaluated to be applicable to skin dosimeters by demonstrating high signal stability, precision, and accuracy in reproducibility and linearity, without cracking due to bending.

• Journal of Bio-Environment Control
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• v.28 no.3
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• pp.218-224
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• 2019

This study was conducted to compare the effect of salicylic acid (SA), an ethylene biosynthesis inhibitor, and the 1-methylcyclopropene (1-MCP) fumigation, to prevent fruit quality deterioration and physiological disorders during the shelf-life of Korea's leading export grape variety 'Campbell Early'. The berries treated with SA after 1-MCP fumigation (1-MCP+SA) showed a higher firmness value and titratable acidity than single treatment of SA or 1-MCP. The rate of shattered berry was high as 41.7% for 100ppm ethephon spray, 40.8% for $25{\mu}M$ SA, and 38.2% for 1,000ppb 1-MCP, but showing only 18.7% when the SA was applied after 1-MCP fumigation. The ratio of short brushes less than 1mm was largest at 74.3% for ethephon treatment, while 1-MCP+SA treatment was found to have the longest brush length among all treatments, with a 2-4mm ratio of 22.8% and a 4-6mm ratio of 27.9%. The weight of rachis was found to be the lowest at 2.3g in the ethephon treatment, and the reduction of rachis weight loss per cluster by 1-MCP+SA treatment was evident. In addition, 1-MCP+SA treatment were effective in mitigating stem browning and berry decay during the 16-day storage period at $19^{\circ}C$ in this cultivar, so it is believed that they can be used as a practical post-harvest treatment in grape exportation.

• 기호학연구
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• no.57
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• pp.121-153
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• 2018

In terms of the story told, we see that Oh! Soojung(Virgin Stripped Bare by Her Bachelors) is a film of the ideololgy of masculinity. However, from the point of view of the manner of presenting story, Oh! Soojung is a film that aims to devalue this ideology. How will it be possible? This is the principle of the irony that the speaker, by saying P, wants to make Q listen that devalues and contradicts P. Our study is tempted to explain the process of interpreting the irony in the film. The ideology of the film occurs when the presupposed contents have become the subject. For example Cendrion who tells a story of a girl married to a prince presupposes that the girl, Cendrion, is obedient. The subject of this story is that the presupposition: /the girls who want to be happy must be obedient/, which represents the ideology of masculinity. Presupposed content thus imposes on the public a collective and conservative value, as its enunciator belongs to the collective voice. Since ironisation occurs when the utterance itself is annulled, one must also deny or cancel the story told of Oh! Soojng: /Jeahun who is rich and Soojung who is obedient and virgin have become lovers/. Since there is no semantic mark within the utterance, irony is a voice that comes from without; this is how we understand irony in a purely pragmatic way. The outer voices are two things: the way to build the story: question of focusing, ocularization and auricularization, and the way to present the story: question the order, the frequency or the plot. Our study is focused on the question of frequency at Oh! Soojung which has a repetition structure in which the memory of Jeahun and that of Soojung are represented one after the other. Since the memories of two characters are not identical, the repetition is accompanied by differences. The differences at first allow the public to build their own story from the di?g?se of the film and then make the audience fall into confusion where we can not be certain of what we see and know in the di?g?se of the film, and finally make their knowledge questionable. About repetition, so that it can have validity in terms of the informativeness of the utterance, it must deny the existence of the previous repetition. This is how repetition cancels itself and consequently the utterance. We see that the irony of Oh! Soojung occurs by repetition with differences that cancels the story of the film.

• Applied Chemistry for Engineering
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• v.29 no.6
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• pp.710-715
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• 2018

In this study, $ZnFe_2O_4@SnO_2@TiO_2$ core-shell nanoparticles (NPs), a photocatalytic material with magnetic properties, were synthesized through a three-step process. Structural properties were investigated using X-ray diffraction (XRD) analysis. It was confirmed that $ZnFe_2O_4$ of the spinel, $SnO_2$ of the tetragonal and $TiO_2$ of the anatase structure were synthesized. The magnetic properties of synthesized materials were studied by a vibrating sample magnetometer (VSM). The saturation magnetization value of $ZnFe_2O_4$, a core material, was confirmed at 33.084 emu/g. As a result of the formation of $SnO_2$ and $TiO_2$ layers, the magnetism due to the increase in thickness was reduced by 33% and 40%, respectively, but sufficient magnetic properties were reserved. The photocatalytic efficiency of synthesized materials was measured using methylene blue (MB). The efficiency of the core material was about 4.2%, and as a result of the formation of $SnO_2$ and $TiO_2$ shell, it increased to 73% and 96%, respectively while maintaining a high photocatalytic efficiency. In addition, the antibacterial activity was validated via the inhibition zone by using E. Coli and S. Aureus. The formation of shells resulted in a wider inhibition zone, which is in good agreement with photocatalytic efficiency measurements.

• Journal of Korea Water Resources Association
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• v.54 no.9
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• pp.719-730
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• 2021

The objective of this study is to develop the water quality and aquatic ecosystem model for Andong lake using SWAT-WET (Soil and Water Assessment Tool-Water Ecosystem Tool) and to evaluate the applicability of WET. To quantify the pollutants load flowing into Andong lake, a watershed model of SWAT was constructed for Andong Dam basin (1,584 km²). The calibration results for Dam inflow and water quality loads (SS, T-N, T-P) were analyzed that average R² was more than 0.76, 0.69, 0.84, and 0.60 respectively. The calibrated SWAT results of streamflow and nutrients concentration was used into WET input data. WET was calibrated and validated for water temperature, dissolved oxygen, and water quality concentration (T-N, T-P) of Andong lake. The WET calibrated results was analyzed that PBIAS was +19%, -13%, +4%, and +26.5% respectively and showed that it was simulated to a significant level compared with the observation data. The observed dry weight (gDW/m²) of zoobenthos was less than 0.5, but the average value of simulation was analyzed to be 0.8, which is because the WET model considers zoobenthos with a broader concept. Although accurate calibration is difficult due to the lack of observed data, SWAT-WET can analyze the effects of environmental change in the upstream watershed on the lake based on long-term simulation based on watershed model. Therefore, the results of this study can be used as basic data for managing the aquatic environment of Andong lake.

• Applied Chemistry for Engineering
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• v.22 no.2
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• pp.196-202
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• 2011

In this paper, a series of alkyl succinic acid esters for base oil were synthesized by condensation reaction of succinic anhydride and fatty alcohol. The structures of the synthesized esters were confirmed by $^1H-NMR$, FT-IR spectrum and GC analysis. Basic properties of esters such as kinematic viscosity (KV), refractive index (RI), total acid number (TAN) and pour points were measured and lubricating properties such as SRV wear scar diameter (SRV WSD), fraction coefficient (COF) and 4-ball wear (4-ball WSD) were also evaluated. As the results of basic properties, KV, RI and pour point of synthetic esters increased as the carbon chain of the esters increased. Measurement value of total acid number (TAN) was indicated between 0.2~4 mgKOH/g, and that metal working fluids and pressure working oils are acceptable to use as base oil. Also, lubricating properties of the esters showed as follows: 0.391~0.689 mm of SRV WSD, 0.110~0.138 of SRV COF and 0.49~0.55 mm of 4-ball WSD depended on the structure of the esters. In a comparison on the lubrication capacity of the SRV test based on polyester TMPTO, SRV WSD result showed that a better performance caused by the alkyl group. On the other hand, SRV COF test was not influenced of the alkyl group which the capacity of the lubricant was sightly diminished than the comparison material, regardless of the alkyl group.